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BACKGROUND The pathologic features of Down syndrome are assumed to be the result of over-expression of genes located on chromosome 21 and/or a more global transcriptional misregulation that crosses chromosomal borders. METHODS To address this issue, four RNA samples from trisomy 21 placentas and four samples from normal first trimester pregnancies were analyzed using Affymetrix U95v2 microarray. Statistical and bioinformatic analyses were employed to compare global gene expression, functional classes, and pathways to differentiate between placentas taken from trisomy 21 and from normal pregnancies. RESULTS About 750 genes were significantly over-expressed in trisomy 21. This list contains an approximately 4.5-fold over-abundance of genes that map to chromosome 21, compared to that which could be expected for this chromosome, on the microarray. Among the classes of genes that best discriminated the trisomy 21 and normal karyotype, we found genes that are also implicated in Alzheimer disease and genes that are associated with ubiquitination and proteosomal degradation. Finally, using the top 10 most discriminating genes, eight samples taken from a different database were correctly classified as either trisomy 21 or normal. CONCLUSIONS Our results demonstrate that gene expression in trisomy 21 affected placentas significantly differs from that of chromosomally normal placentas, and this difference is only partially explained by over-expression of genes from chromosome 21. Our findings suggest that specific highly discriminatory genes may be potential targets for further research and development of novel prenatal diagnosis techniques.

Selective termination is employed in multifetal pregnancies, in the presence of an abnormal fetus, in order to improve the prognosis of the normal fetuses. The term elective reduction is used to describe reduction in twin pregnancies for maternal medical conditions, psychological, or socioeconomic reasons. The purpose of this study was to evaluate the factors that influence outcome in such pregnancies. Eighty-two twin pregnancies underwent selective termination (n = 59) or elective reduction (n = 23) over a 10-year period. Early procedures, performedor = 14 weeks (n = 31), had a pregnancy loss of 9.7% and a mean procedure-to-loss interval of 4.1 +/- 2.8 weeks; mean birthweight was 3299 +/- 395 g in survivors, with a mean gestational age at delivery of 38.4 +/- 2.3 weeks. In comparison, procedures performed14 weeks (n = 51) had a pregnancy loss of 7.8%, with a procedure-to-loss interval of 1.2 +/- 0.6 weeks. Mean birthweight was 2577 +/- 999 g, with a mean gestational age at delivery of 35.7 +/- 5 weeks. In conclusion, outcomes were more favourable among patients who underwent a first trimester procedure. The slight increase in pregnancy loss may be attributed to a higher than expected rate of spontaneous abortions in the first trimester, as manifested by the higher procedure-to-loss interval after a first trimester procedure. These facts underscore the importance of early detection of fetal abnormalities in twin pregnancies by ultrasonography and chorionic villus sampling.

There has been growing concern about the number of multiple gestations resulting from assisted reproductive technologies. For in-vitro fertilization (IVF), there are guidelines concerning the number of embryos to be transferred. In oocyte donation, however, there is a paucity of studies addressing this issue and common practice is extrapolated from standard IVF procedures. This may not be correct since endometrial receptivity has been shown to be altered in oocyte donation. Thus the purpose of this study was to assess the optimal number of embryos to be transferred in oocyte donation. The study population included 254 patients with ovarian failure who underwent a total of 601 embryo transfers in a single shared oocyte donation programme. Pregnancy rates (PRs), multiple pregnancies, triplet pregnancy rates, and implantation rates were evaluated according to the number of embryos transferred. A significant linear increase in PRs was noted with the increasing number of embryos transferred up to five (11.1% for one embryo, 36.7% for five embryos). Multiple pregnancies increased significantly from 15.8% for two embryos transferred, to 44.4% for five embryos. The rate of triplet pregnancies also increased from 2.7% for three embryos transferred, to 8.3% for five embryos. Optimization of the number of embryos to be transferred is discussed.

The fourth to eighth in-vitro fertilization cycles of patients who had previously reached the stage of embryo transfer without conceiving were evaluated. A total of 426 cycles were received in women ranging in age from 25 to 46 years. The patients underwent from four (169 women) to eight (27 women) treatment cycles, using four established protocols for induction of ovulation. There was no statistical difference in the age, aetiology, duration of infertility and distribution of the various protocols among the analysed groups. The pregnancy rates in cycles 4-8 were 19.5, 15.4, 10.8, 16.7 and 11.8% respectively (mean 16.2% per cycle) and were not statistically different. There was no trend of reduced success when the number of attempts increased. The overall live birth rate was 12.4%. The pregnancy rate was comparable between age groups. No protocol proved to be significantly superior to others when pregnancy rate per embryo transfer was assessed. We concluded that the pregnancy rate in cycles 4-8 was stable, including those of patients up to 42 years of age. Continuous efforts are therefore advised for at least up to this age and number of attempts. A change of an induction protocol in subsequent cycles, after repeated failure, is not statistically justified.

During a 5.5 year period, 309 clinical pregnancies were recorded in our in-vitro fertilization (IVF) unit. A single gestational sac was identified by early ultrasonography in 233 patients, while in 76 others, multiple gestational sacs were noted. 'Take-home baby' rate, in patients in whom multiple sacs were observed, was higher than that in patients with a single sac. Delivery of at least one live newborn occurred in only 73.8% of patients with a single sac, compared with 93.3% and 91.7% in patients with two and three gestational sacs, respectively. Conversely, the early and late abortion rates were decreased in patients with multiple sacs. Embryonic implantation rate, defined as the ratio of gestational sacs observed to the number of embryos transferred, was found to be a valuable prognostic factor for a live delivery, and can serve as a tool in assaying the prognosis of pregnancy detected by early sonography. The observation of a higher 'take-home baby' rate in cases with multiple sacs identified by ultrasound and with higher embryonic implantation rate, might be the result of a better embryo quality and/or improved uterine receptivity, promoted by a favourable hormonal milieu or by as yet unknown endometrial factors.

Multifetal pregnancy reduction (MFPR) appears to be an efficacious method for improving the perinatal outcome of 'high order' multifetal gestations. The present study was undertaken to evaluate pregnancy outcomes after MFPR to twins in comparison with spontaneously conceived twins. In all, 10 patients with quadruplet gestations (group 1) and 30 patients with triplet gestations (group 2), who underwent MFPR to twins, were prospectively enrolled. Pregnancy complications, gestational age at delivery, mode of delivery and birthweights were compared with 30 consecutive spontaneous twin gestations (group 3) matched by maternal age and parity. Mean gestational age at delivery and mean birthweights were significantly lower in group 1, compared with groups 2 and 3 (33.2, 35.9, 36.9 weeks, and 1843, 2209, 2361 g respectively). The incidence of pregnancy complications was significantly higher in group 1 compared with group 3. There was also a dear trend of increased incidence of specific pregnancy complications in group 1 compared with groups 2 and 3, especially premature contractions (PMC; 50, 27 and 13% respectively), and pregnancy-induced hypertension (PIH; 40, 23 and 7% respectively). In conclusion, the initial number of fetuses before reduction was inversely correlated with gestational age at delivery and birthweight, and positively correlated with pregnancy complications. Contrary to previous studies, we found a higher incidence of pregnancy complications after MFPR compared with spontaneous twins, especially PMC and PIH.

The coexistence of an in-vitro fertilization (IVF) pregnancy and genital tuberculosis may pose life-threatening consequences. This case report describes catastrophic dissemination of latent genital tuberculosis, followed by IVF and pregnancy. The role of both IVF manipulation and the pregnancy itself in the exacerbation of latent tuberculosis is discussed. In addition, some measures for the detection, follow-up and treatment of latent genital tuberculosis in patients who undergo IVF are proposed.

A retrospective analysis of ovarian hyperstimulation syndrome in high responders undergoing in-vitro fertilization (IVF) is presented. High responders were defined as having > 20 follicles and serum oestradiol > 3000 pg/ml after treatment with human menopausal gonadotrophin. Of the initial 30 IVF cycles in high responders, 23 developed a moderate-to-severe ovarian hyperstimulation syndrome (76.7%). Subsequently, 15 other IVF cycles in high responders were combined with a repeated aspiration of ovarian follicles and corpus luteum cysts just prior to embryo transfer. Only three patients (20%) developed a moderate ovarian hyperstimulation syndrome (P = 0.0004). We conclude that repeated follicular aspiration is safe and results in a significant reduction in the incidence and severity of this condition in high responders undergoing IVF.

A total of 30 patients with multifetal pregnancies, all resulting from treatment with superovulatory agents or assisted reproductive techniques, underwent embryo reduction. All patients had three or more fetuses (one sextuplet, two quintuplets, seven quadruplets and 20 triplets). The procedure was carried out using intra-embryonal injection of 0.9% sodium chloride solution. Embryo reduction was carried out via the transabdominal approach in 10 patients, performed at 11-12 weeks of gestation, and via the transvaginal route in 20 other patients, at 8-10 weeks of gestation. In the transabdominal group, one patient aborted following repeated attempts at embryo reduction while the other nine gave birth to healthy newborns (eight twins and one triplet). In the transvaginal group, four pregnancies are currently ongoing (all beyond 28 weeks of gestation), 14 pregnancies resulted in a delivery of at least one live newborn (13 twins and one singleton), one patient had a late abortion at 24 weeks' gestation and another was delivered at 27 weeks' gestation due to severe pre-eclampsia. Transvaginal ultrasound-guided needle procedures are commonly practised in most in-vitro fertilization units. The employment of this route for embryo reduction, performed at an earlier gestational age and with the use of a non-toxic substance such as 0.9% saline solution, is advocated.

Ovarian hyperstimulation syndrome may be a serious complication of ovulation induction usually manifested by ovarian enlargement and ascites. In its severe form, haemoconcentration, oliguria and hydrothorax may ensue. As evident from this case report, the usual sequence of events does not necessarily occur in all cases. Unilateral hydrothorax may be the only extra-ovarian manifestation of ovarian hyperstimulation syndrome.